Combined clamp release and motion stop for duplicators



June 8,1937. STQRCK 2,083,044

COMBINED CLAMP RELEASE AND MOTION STOP FOR DUPLICATORS Filed July 2,1936 2 Sheets-Sheet 1 F. w. s-roRc'K June 8, 1937. 2,083,044

COMBINED CLAMP RELEASE AND MOTION STOP FOR DUPLICATORS Filed July 2,1936 2 Sheets-Sheet:

Patented June 8, 1937 UNITED STATES PATENT OFFICE COMBINED CLAMP RELEASEAND MOTION STOP FOR. DUPLICATORS Application July 2, 1936, Serial No.88,568

Claims.

This invention relates to rotary duplicators of the type having aprinting cylinder or platen which is provided with a clamping deviceadapted to secure a master copy sheet to the face of the platen, and theprinting platen is further provided with a determinate stopping andstarting point for each cycle of operation and the invention moreparticularly relates to a combined automatic clamp actuating device andreverse motion stop which is eiiective to stop the platen in adeterminate position other than its normal operative stopping andstarting point and efl'ective only when the platen is rotated contra toits normal direction of operative rotation.

In duplicators of the herein referred to character, the end of themaster copy sheet is secured to the printing platen and the normalstopping point of the platen arranged relative to a bight, formed by theplaten and a coacting pressure roller, so that clear sheets to beduplicated upon may be fed into said bight to register in engagementwith the master copy upon subsequent rotation of the platen and themaster matter duplicated upon the clear sheet. A duplicating machine ofthis referred to character is iully shown and described in my U. S.Letters Patent Re. No. 19,951.

Accomplishment of the desired function of feeding the clear sheets forregistering engagement with the master copy requires an arrangement ofthe machine elements that will effect a stopping point for the clampedend of the master close to the path oi. the advancing end of the clearsheet to be duplicated upon so as to register with the master with aminimum unused end margin. This requires that the clamped end of themaster and the advancing front end of the clear sheet register forengagement in the afore said bight formed by the printing platen andpressure roller. in arranging the machine elements to obtain the desiredduplicating function in an efficient and desired sequence, the aforesaidnormal operating position of themaster clamp is either in aninaccessible position or in a position which does not readily lenditself for the purpose of conveniently and properly attaching the mastercopy or removing the same from its clamp without interference.

When the master copy is to be attached or removed, in duplicatingmachines having these aforementioned elements and so arranged, theoperator rotates the drum until the clamp is in an exposed or desiredposition with the master copy free from contact with the pressureroller.

55 In performing this positioning operation, the

platen is usually rotated contra to its normal direction of operativerotation and its stopping point controlled manually by the operator,therefore, care and particular attention must be exercised by theoperator to stop the clamping device in the desired or exposed position.This positioning operation is further inconvenienced when the duplicatoris operated by motor or like power and at a relatively high speed. Underthese circumstances, unless the operator is alert, the platen willcontinue rotating until it is again engaged in its normal stop position.

it is obvious that speed, convenience and simplicity in operation are ofvital importance in duplicating machines of this referred to character.

Accordingly, a primary object of my invention is to provide a simple andefficient stop for a duplicator and which is contained wholly within theprinting platen or drum and thus eliminates outward rotating projectionsor extensions.

Another object of my invention is to provide a combined automatic stopand clamp release which is effective to arrest rotary movement of theprinting platen or drum in one direction only and at a point other thanits operating cycle stopping point, andpwhereby the clamp issimultaneously opened in a convenient position to permit the removal andinsertion of the master copy sheet.

A still further object of my invention is, to provide a combinedduplicator platen stop and clamp opening device of a rugged constructionand with a minimum number of working parts.

With the above and other apparent objects in view, my inventioncomprises a novel combination and arrangement of parts hereinafterdascrib'ed and more specifically pointed out in the appended claims. 7

In the accompanying drawings .i have illustrated a preferred form of mycombined automatic stop and clamp actuating device, embodied withaportion of a rotary duplicator, sufficient to enable those skilled inthe art to understand the construction and operation thereof.

Referring to the drawings:

Fig. 1 is a transverse section of a duplicator having my improvementsembodied therewith.

Fig. 2 is a detached, enlarged transverse section of the duplicatorplaten or drum and its 'coacting pressure roller.

Fig. 3 is a view corresponding substantially to Fig. 2, but shows theparts in a different position.

Fig. 4 is a fragmentary view of one end oi the printing platen or drum..

Fig. 5 is a sectional view taken substantially along line 5-5, Fig. 3.

Fig. 6 is a sectional view taken substantially along line 84. Fig. 3,and

Fig. 7 is substantially a diagrammatical view showing the comparativepositions of the master clamp as illustrated at Figs. 2 and 3.

The duplicating machine The duplicating machine, of which a portion onlyis illustrated, is provided with opposed side frames 10, only one ofwhich is shown. The frames are retained in a spaced relation by suitablecross members such as illustrated at Ii and I2.

The printing platen or drum I3 is rotatably mounted upon a shaft 14which, in turn, is secured against rotation in suitable hearings in theside frames.

A'pressure roller it engages the peripheral face of the platen l3 and ismounted upon a shaft it which is journalled at its ends in suitablebearings in the side frames.

The feed rollers l1, I! are each provided with shafts I8, 20 which arerotatably supported in suitable bearings. In this instance, .the rollerI1 is utilized as an intermediate moisture applicator which is suppliedwith moisture by a wick II which engages with fluid contained in thetank 22.

The printing platen is rotated by suitable mechanism, not shown, toeffect a determinate positioned stop or dwell period in its cycle ofrotation. The duplicator parts are illustrated at Fig. 1 in thisreferred to stop or dwell position. A drive gear 23 is secured inrelation to the printing platen l3 and is rotated therewith.

This drive gear 28 meshes with an intermediate gear 24 which, in turn,meshes with a pinion 25 which rotates the feed roller I I and thus thefeed rollers I 1, II are rotated in a direct relation to the printingplaten.

The master copy sheet clamp The periphery of the printing platen I3 isprovided with a recess which extends longitudinally thereof and isadapted to receive and support a clamp bar 26. The outer face of theclamp bar 2! conforms to the contour of the platen face and forms a partthereof. This bar 28 is of less width than the drum recess and isadapted for a transverse sliding movement within the platen recess. Thebar 28 is retained seated in the platen recess by means of springs 21disposed in recesses in the opposed end faces of the platen. Afragmentary view of one end of the platen with the clamp bar 28 attachedthereto by means of the springs 21 is illustrated at Fig. 4. Theopposite end of the clamp bar is secured to the platen in a like manner,one end of the spring 21 is attached to a stud 28 fixed in the end ofthe clamp bar and the opposed end of said spring attached to a stud 20fixed in the platen end. I

The side wall 20a of the clamp bar 28 is urged toward and against theside wall Ila of .the platen recess by means of compression springs lldisposed in bores in the clamp bar, the inner ends of said springshaving their bearings against the bottom ofi'qshe bores and theiropposed ends bearing against the side wall no of the platen recess.

In this instance, the clamp bar 28 is provided with projections 3| whichextend into the These projections ii are adapted to be engaged by a camelement which, as illustrated, is in the form of a rod 32 rotatablysupported within the drum. This rod is cut away as at 32a to form asubstantially straight face and which is disposed opposite to the clampbar projections 3|. Rotation of the rod 32 causes the high part thereofto bear against the projections 3i and continued rotation of the rodwill cause the bar 28 to compress the springs 30 and thus separate theclamping walls Ila and 26a as illustrated at Fig. 3.

A duplicating machine and clamping device of the above description arecompletely shown and described in my aforementioned Letters Patent Re.No. 19,951, therefore, further detailed description is thoughtunnecessary as the important elements thereof will be further mentionedin connection with my improvements.

The combined automatic reverse motion stop and clamp opening deviceSecured to the cam rod 32 is a cam follower 33 which engages with astationary cam 34 secured to the stationary shaft H which rotatablysupports the printing platen H. The cam follower 33 is retained in closeengagement with the periphery of the cam 34 by means of a flat spring 35which, in this instance, is secured to the rod 32 and has a bearingagainst the shaft ll. In my preferred illustrated form, the peripheralface of the cam 3 is provided with a notch 34a. for a purposehereinafter described.

Rotation of printing platen during duplicating operation The edge of themaster copy sheet 0, which is clamped between the platen wall In and theclamp bar wall 26a and in its normal position, to begin a cycle ofoperation, is depending as shown at Fig. 1.

The clear sheet to be duplicated upon is positloned in the bight of thefeed rollers IT, IS and the printing platen I! is then rotated. in thedirection of arrow 11 and, through the gearing connections 23, 24, 25,the feed rollers advance the clear sheet for registering engagement withthe master copy under pressure exerted by the roller i5. As the printingplaten I3 is rotated in its normal direction for duplicating, asindicated by arrow 0, the cam follower 32 rides around the cam 34 and inengagement with the peripheral face thereof. As will be noted, the faceof the cam 34 is provided with a low area ub, adjacent one wall of thenotch a, and is inclined to the greater diameter of the cam whichterminates at 34c and connects with the wall "I of the notch Ila. I haveprovided a bumper e which, in this instance, is in the form of aresilient roller rotatably supported adjacent the cam face and notch a.This bumper e prevents undue noise or slap as the cam follower II dropsfrom the high surface to the low surface of the cam face adjacent thecam notch it.

During normal rotation of the printing platen It, the rod 32 receives aslight oscillating movement but which is ineffective to engage the clampbar projections, due to the clearance provided by the cut-away portions32a of the rod I2 and which are disposed opposite to the camprojections. Operation of combined reverse motion stop and clamp openingdevice To position the master copy clamp for conveniently removlngorreplacing the master copy sheet, the printing platen is rotated contrato its normal operative direction as indicated by arrow b, Fig. 3. Thecam follower 83 rides on the depressed area 34b of the cam until the end33a abuts against the notch wall 341 and continued rotation of theplaten causes the cam follower end 33a to enter the notch and engagewith the opposite notch wall 349 and thereby wedging the cam follower 33in the cam notch 3441, see Fig. 3. I

During the rotative movement of the cam follower 33, in the cam notch34a, the rod 32, to which the follower is secured, is rotated therewithand the cam point 320 of the rod 32 engages with the clamp barprojections 3| and forces the bar 26 to slide in its recess against theaction of the bar springs 30 and thus causing the clamp walls l3a, 26ato separate, see Figs. 3 and '7, so that the edge of the master copysheet may be readily and conveniently removed or replaced.

While the clamp is in this open position, the edge of the master copysheet may be inserted between the clamping walls and against the bottomof the platen recess; the platen is then rotated in its normaldirection, indicated by arrow a. As the cam follower 33 disengages fromthe cam notch, see Fig. 2, the clamp bar projections 3| are disengagedfrom their contact with the cam rod 32 and the springs 30 again slidethe bar into engaging position with the edge of the master copy sheetclamped between the walls Ha, 26a.

While I have shown and described a preferred embodiment of my invention,it is to be understood that this is for the purpose of iliustration onlyas my device is capable of many modificaiions and varied applications.Changes. therefore, in the construction and arrangement. may be madewithout departing from. the spirit and scope of the invention, asdisclosed in the appended claims, in which it is my intention to claimall novelty inherent in my invention as broadly as possible, in View oithe prior art.

Having thus described my invention, what I claim is:

1. A rotary duplicator of the character described having a rotatableprinting platen and means for rotating Said platen in oppositedirections, a yielding clamp member for securing a master copy sheet tosaid platen, an extension associated with said clamp and positionedwithin said platen, an element within said platen which is adapted toengage with said extension, a fixed member disposed within said platenand in the path of said element with means associated with said memberwhereby said element engages therewith to simultaneously open said clampand arrest rotative movement of said platen at a determinate pointonlywhen said platen is rotated in one direction.

2. ,A rotary duplicator of the character described having a rotatableprinting platen with v means for securing a master copy sheet theretoand means for rotating said platen in opposite directions, an elementpivotally secured within said platen and rotatable therewith, a membersecured to said element, a second member fixedly disposed within saidplaten and in the path of said first member with means associated withsaid second member whereby said first member engages therewith to arrestrotative movement of said platen at a determinate point only when saidplaten is rotated in one direction.

3. A rotary duplicator of the character described having in combinationa rotatable printing platen with means for rotating said platen inopposite directions, a recess in the peripheral face of said platen andextending longitudinally thereof, a clamp for securing a master copysheet to said platen, said clamp including a clamp bar disposed in saidrecess and substantially flush with the peripheral face of said platen,a rotatable element disposed within said platen and associated with saidclamp bar to control the positioning thereof, a stationary elementwithin said platen and which is adapted to coaet with said rotatableelement to open said clamp'and simultaneously arrest rotative movementof said platen in one direction, said element being ineffective when thesaid platen is rotated in its opposite direction.

4. A rotary duplicator of the character described having a rotatableprinting platen and means for rotating said platen in oppositedirections, a yielding clamp member for securing a master copy sheet tosaid platen, an extension associated with said clamp and engaging withinsaid platen, a member pivotally secured to and disposed within saidvplaten, said member being adapted to be operatively engaged with saidclamp extension, said pivoted member including an extending portion, afixed member disposed within said platen and in the path of saidextending portion, an aperture in said fixed memher, said aperture beingadapted to operatively engage with said extending portion only when saidplaten is rotated in one direction and whereby further rotative movementof the platen in that direction is arrested and said clamp issimultaneously opened.

5. A rotary duplicator of the character described having a rotatableprinting platen and means for rotating said platen in oppositedirections, a yielding clamp member for securing a master copy sheet tosaid platen, a member pivotally secured to and disposed within saidplaten, said pivoted member including an extend ing portion, a'fixedmember disposed within said platen and in the engaging path of saidpivoted member portion, an aperture in said fixed memher, said aperturebeing adapted to operatively

